Logging In to the System as root

Before you install the Oracle software, you must complete several tasks as the root user. To log in as the root user, complete one of the following procedures:
Note:
You must install the software from an X Window System workstation, an X terminal, or a PC or other system with X server software installed
Following are the steps for installing the software from an X Window System workstation or X terminal:
1. Start a local terminal session, for example, an X terminal (xterm).
2. If you are not installing the software on the local system, then enter the following command to enable the remote host to display X applications on the local X server: $ xhost fully_qualified_remote_host_name
3. For example: $ xhost somehost.us.example.com
4.
5. If you are not installing the software on the local system, then use the ssh, rlogin, or telnet command to connect to the system where you want to install the software: $ telnet fully_qualified_remote_host_name
6.
7. If you are not logged in as the root user, then enter the following command to switch user to root: $ sudo sh
8. Note: for above to work username needs to be on shudder, if needed following these:
9. su -c visudo
10. it will open the file /etc/sudoers
11. then
12. copy the line with yy command
13. root ALL=(ALL) ALL
14. and rename it to
15. “username u want to add” ALL=(ALL) ALL
16. save the file
17. now u r in sudo

So on our system we got 5Gs that should be plenty for our small test systems If the size of the RAM is less than the required size, then you must install more memory before continuing.
The following table describes the relationship between installed RAM and the configured swap space recommendation:
Quick Note:
On Linux, the HugePages feature allocates non-swappable memory for large page tables using memory-mapped files. If you enable HugePages, then you should deduct the memory allocated to HugePages from the available RAM before calculating swap space.

Available RAM Swap Space Required
Between 1 GB and 2 GB 1.5 times the size of the RAM
Between 2 GB and 16 GB Equal to the size of the RAM
More than 16 GB 16 GB

To determine whether the system architecture can run the software, enter the following command:

[root@rhel6 ~]# uname -m
x86_64
[root@rhel6 ~]#

another quick note:
This command displays the processor type. Verify that the processor architecture matches the Oracle software release to install. If you do not see the expected output, then you cannot install the software on this system.

on my RHEL implementation was no necessary but If in your it’s, then quickly
follow 6.2.3 Creating a Swap File from RHEL 6 docs
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/s2-swap-creating-file.html
To add a swap file:
1. Determine the size of the new swap file in megabytes and multiply by 1024 to determine the number of blocks. For example, the block size of a 64 MB swap file is 65536.
2. At a shell prompt as root, type the following command with count being equal to the desired block size: dd if=/dev/zero of=/swapfile bs=1024 count=65536
3. Setup the swap file with the command: mkswap /swapfile
4. To enable the swap file immediately but not automatically at boot time: swapon /swapfile
5. To enable it at boot time, edit /etc/fstab to include the following entry: /swapfile swap swap defaults 0 0 The next time the system boots, it enables the new swap file.
6. After adding the new swap file and enabling it, verify it is enabled by viewing the output of the command cat /proc/swaps or free.

To determine the available RAM and swap space, enter the following command:
# free

Important Note:
Oracle recommends that you take multiple values for the available RAM and swap space before finalizing a value. This is because the available RAM and swap space keep changing depending on the user interactions with the computer.
Contact your operating system vendor for swap space allocation guidance for your server. The vendor guidelines supersede the swap space requirements listed in this guide.
Automatic Memory Management
Starting with Oracle Database 11g, the Automatic Memory Management feature requires more shared memory (/dev/shm)and file descriptors. The shared memory should be sized to be at least the greater of MEMORY_MAX_TARGET and MEMORY_TARGET for each Oracle instance on that computer.
To determine the amount of shared memory available, enter the following command:
# df -h /dev/shm/

Another note:
MEMORY_MAX_TARGET and MEMORY_TARGET cannot be used when LOCK_SGA is enabled or with HugePages on Linux.

Disk Space Requirements
The following are the disk space requirements for installing Oracle Database 11g Release 2 (11.2):
At least 1 GB of disk space in the /tmp directory
To determine the amount of disk space available in the /tmp directory, enter the following command: # df -h /tmp

We’re all good here or we shall see later on on the install… process… if need your sys admin will assist you with this or at least mine does…. 😉
If there is less than 1 GB of free disk space available in the /tmp directory, then complete one of the following steps:
Delete unnecessary files from the /tmp directory to meet the disk space requirement.
Set the TMP and TMPDIR environment variables when setting the oracle user’s environment.
Now let’s make sure we the least require space using #df -h

Additional disk space, either on a file system or on an Oracle Automatic Storage Management disk group is required for the fast recovery area if you choose to configure automated backups.

Checking the Software Requirements

Depending on the products that you intend to install, verify that the following softwares are installed on the system, but since we’re focusing on 11gR2 on RHEL 6.3 then we’ll just jump into it…

Note:
Oracle Universal Installer performs checks on the system to verify that it meets the listed requirements. To ensure that these checks pass, verify the requirements before you start Oracle Universal Installer.

another note:
Only the distributions and versions listed in the earlier list are supported. Do not install the software on other versions of Linux.

Kernel Requirements

The following are the kernel requirements for Oracle Database 11g Release 2 (11.2):
….. We’re interested on:
On Red Hat Enterprise Linux 6
2.6.32-71.el6.x86_64 or later
….
To determine whether the required kernel is installed, enter the following command:
# uname -r

root@rhel6 ~]# uname -r
2.6.32-279.el6.x86_64
[root@rhel6 ~]#

Package Requirements

Package – RPM Quick Note:
Starting with Oracle Database 11g Release 2 (11.2.0.2), all the 32-bit packages, except for gcc-32bit-4.3, listed in the following table are no longer required for installing a database on Linux x86-64. Only the 64-bit packages are required. However, for any Oracle Database 11g release before 11.2.0.2, both the 32-bit and 64-bit packages listed in the following table are required.

The following or later version of packages for Oracle Linux 6, and Red Hat Enterprise Linux 6 must be installed, or at least these were installed on our test system:
use following command to check all install package are in place:
–Us this command to give you nice sorted list one the packages.

As you can see I have all the require packages for our 86_64 bit (64bit) os system, so that why you don’t see many i386 rpms, if in your case you’re missing any or several packages then I recommended to use RHEL software manager utility to add these, the reason I recommend this way is because you can search for the missing packages the manager will present you with the most to update version instead of just installing these manually but that’s just me and it’s only a personal choice…

Compiler Requirements

Intel C++ Compiler 10.1 or later and the version of GNU C and C++ compilers listed under “Package Requirements” are supported with these products.

Oracle ODBC Drivers

You should install ODBC Driver Manager for UNIX. You can download and install the Driver Manager from the following URL:
http://www.unixodbc.org
To use ODBC, you must also install the following additional ODBC RPMs, depending on your operating system:
On Oracle Linux 6 and Red Hat Enterprise Linux 6:
in our test case we have the unixODBC drivers:

Oracle JDBC/OCI Drivers

Use JDK 6 (Java SE Development Kit 1.6.0_21) or JDK 5 (1.5.0_24) with the JNDI extension with the Oracle Java Database Connectivity and Oracle Call Interface drivers. However, these are not mandatory for the database installation. Note that IBM JDK 1.5 is installed with this release.

Network Setup

DNS
Verify the value of the DNS configuration file /etc/resolv.conf. The nameserver must be not set or set to a valid DNS server and you can add the two time-out parameters.

Disable secure linux

Disable secure linux by editing the /etc/selinux/config file, making sure the SELINUX flag is set as follows:
SELINUX=disabled
Alternatively, this alteration can be done using the GUI tool.

Creating Required Operating System Groups and Users

The following local operating system groups and users are required if you are installing Oracle Database:
The Oracle Inventory group (typically, oinstall)
The OSDBA group (typically, dba)
The Oracle software owner (typically, oracle)
The OSOPER group (optional. Typically, oper)

To determine whether these groups and users exist, and if necessary, to create them, follow these steps:

To determine whether the oinstall group exists, enter the following command:
# more /etc/oraInst.loc
[root@rhel6 ~]# more /etc/oraInst.loc
/etc/oraInst.loc: No such file or directory
[root@rhel6 ~]#
If the output of this command shows the oinstall group name, then the group exists.
If the oraInst.loc file exists, then the output from this command is similar to the following:
inventory_loc=/u01/app/oraInventory
inst_group=oinstall
The inst_group parameter shows the name of the Oracle Inventory group, oinstall.
To determine whether the dba group exists, enter the following command:
# grep dba /etc/group
If the output from this commands shows the dba group name, then the group exists.
so our case we need create all new:
Let’s create the oinstall and dba groups and oracle/software user:

After updating the values of kernel parameters in the /etc/sysctl.conf file, either restart the computer, or run the command sysctl -p to make the changes in the /etc/sysctl.conf file available in the active kernel memory.

Check Resource Limits for the Oracle Software Installation Users
For each installation software owner, check the resource limits for installation, using the following recommended ranges:

If necessary, update the resource limits in the /etc/security/limits.conf configuration file for the installation owner. For example, add the following lines to the /etc/security/limits.conf file:

One more note:
The values mentioned in this example are illustrative and not actual values that must be added.
When the limits.conf file is changed, these changes take effect immediately. However, if the grid or oracle users are logged in, then these changes do not take effect until you log these users out and log them back in. You must do this before you attempt to use these accounts to install.

Add or edit the following line in the /etc/pam.d/login file, if it does not already exist:

session required pam_limits.so

Creating Required Directories

Create directories with names similar to the following, and specify the correct owner, group, and permissions for them:
The Oracle base directory
An optional Oracle data file directory
The Oracle base directory must have 3 GB of free disk space, or 4 GB of free disk space if you choose not to create a separate Oracle data file directory.

To create the Oracle base directory:
1. Enter the following command to display information about all mounted file systems:
df -h

Hostname on Multi homed/Alias computer

Oracle database can be installed on:
A multihome computer. It is associated with multiple IP addresses. This is typically achieved by having multiple network cards on the computer. Each IP address is associated with a host name. In addition, you can set up aliases for the host name.
A computer with multiple aliases: it is registered with the naming service under a single IP but with multiple aliases. The naming service resolves any of those aliases to the same computer.
Before installing Oracle Database on such a computer, set the ORACLE_HOSTNAME environment variable to the computer whose host name you want to use. Oracle Universal Installer uses the ORACLE_HOSTNAME environment variable setting to find the host name. If ORACLE_HOSTNAME is not set and you are installing on a computer that has multiple network cards, then Oracle Universal Installer determines the host name from the /etc/hosts file.
Example of /etc/hosts file with rhel6.urimagination.local as hostname

Clients must be able to access the computer either by using this host name or by using aliases for this host name. To verify this, ping the host name from the client computers using the short name (host name only) and the full name (host name and domain name). Both tests must be successful.
Use the following procedure to set the ORACLE_HOSTNAME environment variable. For example, if the fully qualified host name is somehost.us.example.com, then enter the following commands for the Bourne, Bash, or Korn shell as on the following example .bash_profile file for our test system.

Configuring the oracle User’s Environment

Set the ORACLE_BASE for oracle base directory and ORACLE_SID environment variables. Add the following lines to bash_profile file:

Software Availability and Installation

Oracle Database 11g Release 2 (11.2.0.3) is available in the latest media pack. You can also download the software from My Oracle Support Web site:
So we’ll be doing full implementation strait to 11g R 2 .0.3
To download the software from My Oracle Support:
1. Log on to My Oracle Support.
2. Click Patches & Updates.
3. In the Patch Search section, click the Search tab.
4. Enter 10404530 in the patch number field.
5. Select a platform to download.
6. Click Search.
7. In the Patch Search Results page, under Patch Name, click the patch number to display the patch details.
8. Click Download.
9. From the File Download window, click each file name to download the selected software.
Installation Type Zip File

then fix with:
To increase or decrease /dev/shm filesystem size
1) as root Open /etc/fstab with vi or any text editor of your choice,
2) Locate the line of /dev/shm and use the tmpfs size option to specify your expected size,
The /etc/fstab content format is documented in man fstab and the tmpfs filesystem options can be found in man mount

3) To make change effective immediately, run this mount command to remount the /dev/shm filesystem:

Then continue with Management Options: default
Database Storage: default
Backup and Recovery:/u01/app/oracle/recovery_area
Schema Passwords: use same password for all
Operating System Groups: user dba for all

at the checking system phase the installer might complain about 2 packages: